M20 Oil Pressure

Biscuit · Post by **Biscuit** » Sun Feb 27, 2005 5:05 pm

John, put it back to standard, do not worry about it and ENJOY.

Eric · Post by **Eric** » Sun Feb 27, 2005 5:37 pm

Lawrence yes you could say I was having a bad day. The thing is my long answer was probably the most comprehensive I have ever given and it took a long time to type and think about all of the possible reasons for the low / zero oil pressure. Then when John gave his more comprehensive reply it seemed he already knows almost everything there is to know about the oiling system but should have told us this up front. Even now I have been phoning a few people to get other opinions. I agree with Alan really put it back to correct standard and throw the gauge away. I have never had a gauge on my engine but sometimes just for a little re-assurance I grasp the external filter cartridge I have fitted to the end of the filter tunnel and check if it swells and throbs when I open the throttle. When it swells and throbs everything is OK. By the way with this filter attached you have to be a little carefull its possible to generate enough pressure when cold to open up a leak in the rolled seam where the end flange of the cartridge is joined to the can. So you dont start it and blip the throttle wide for a minute or two, not that you should do anyway.

autosprink · Post by **autosprink** » Mon Feb 28, 2005 5:49 am

Sorry if you find my post time wasting - I took advice on the oiling system modification from a guy who has raced these engines over many years with a lot of success. I think that AMC finished up with a continous oil supply to the overhead gear with a similar arrangement . As I said I blocked the oil supply temporally to the top end and it made no difference so I dont think that this is the reason for no oil pressure. Yes one of the first things I did was have the gauge checked. It is a new 65mm stainless oil damped gauge. However I will persevere and let you know what I find (if you are still interested) Prior to modifing the oil system the bike had the same problem.

Regards

John Powell

Regards

John Powell

Biscuit · Post by **Biscuit** » Mon Feb 28, 2005 11:13 am

John, YOU ARE NOT TIME WASTING, anything that others are up to, and learning things, benefits us all.

TommoT · Post by **TommoT** » Mon Feb 28, 2005 11:38 am

Just a quick comment.

First of all I don't anything about the twins, running a G80 myself. Just to put my comment into perspective.

Reading all of the posts, it suddenly struck me. Could it be that John has fitted the guage in such a way that:

- the measurements are taken off the relief valve? When the oil is cold and thick as syrup, it will press oil through the relief valve, thus giving a reading. When the oil is hot the relief valve closes, and presto no reading!

- the guage requires a minimum pressure, that the oil pump cannot and does not need to deliver when hot.

I have heard other long time owners of twins guote around 40 psi at idle and 60 psi running pressure.

Sorry for my ramblings, but any subject on the twins interests me as I hope one day to be able to buy one.

Regards,
Tom M. (TM)

lawrence · Post by **lawrence** » Mon Feb 28, 2005 5:30 pm

Hi all
I don't think Eric meant to imply that John shouldn't bother us. Eric has always been really helpful and is an all round good guy. He even asked the Salvation Army to save a bad girl for him.

Sometimes when I type things I later see that they can be misinterpreted. If I know what I mean I expect everyone else to. D'oh! Keep the topics coming John. Like Alan says, everything is useful. If people don't want to get involved they will ignore it, eg. my posts [:(]

Eric, did you know you can type off line and reconnect to send it? Saves money!!

Lawrence [}:)]

autosprink · Post by **autosprink** » Tue Mar 01, 2005 6:19 am

Erics's post didn't annoy me. It takes more that that to upset us colonials. I probably should have detailed the extent of my "experiments" prior to asking the question. However I thought someone might have had experience with the problem. As I said I will be away at the NZ Jampot rally in Hamner Springs in the South Island for a week so if I you dont hear from me for a while I haven't got the huff - I propose to rig up a pressure device to pressurise the oil system while the engine is stationary - maybe that will tell me something. Maybe there is nothing wrong at all. With regard to Tom's post, The oil pressure is taken from the oil filter chamber and I wondered if the filter relief valve was causing a false reading so I removed the filter and filter relief (item 5 Fig 3 in Neills Book)- no different
Regards
John Powell

m knight. · Post by **m knight.** » Tue Mar 01, 2005 10:04 pm

Triumph use to fit an oil preasure guage but later removed it as the crank would set up an effect where the crank would work like a centrifuge, the preasure would often show close to zero sending owners back to their dealers in a panic.This situation wasent helped by the poor pump employed and I suspect that the longer the stroke the more pronounced this effect would become.
P.S I have never witnessed this effect, I read about it years ago in a bike magazine![?]